Kirsten flew across the world to have a baby. Then the doctor said her last embryos had disappeared.

When Kirsten McLennan and her husband Ryan decided to have a baby, they didn't expect it to take six years, three countries, and a third party to get there.

"We were in our early 30s. We had no fertility issues that I was aware of then, and so we just expected it to happen quite quickly," says Kirsten. 

But nine months passed with no pregnancy. Confused and frustrated, the couple decided to visit a fertility specialist.

"Ryan had his sperm checked, I had my egg count and quality checked, and everything came back normal."

A subsequent scan revealed Kirsten had polycystic ovaries, which can impact fertility. She was prescribed Clomid, but after three cycles, she was no closer to a pregnancy. 

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"So we then tried IUI (intrauterine insemination). I did three rounds of IUI, still no pregnancy."

Next came the gruelling process of IVF (in vitro fertilization). 

"My first IVF transfer failed, which is quite common for the first transfer."

The second resulted in a "pregnancy of unknown location" — an embryo that had implanted somewhere in Kirsten's body but not in her uterus. It wasn't ectopic, but it wasn't viable either.

She was given methotrexate — a chemotherapy agent — to end the pregnancy. "It was a really difficult experience."

After that, things kept going wrong. "My cycles kept getting cancelled, and the reason was I had this thin endometrium lining. I had absolutely no idea what the endometrium lining was and why it was important."

She soon learned that this lining was crucial to falling pregnant and, importantly, staying pregnant. 

"For a transfer in Australia, the requirement is six millimetres or more … and mine was always in the fours."

When the lining hit the fives, her clinic went ahead. "They were like, well, close enough is good enough. And they would go ahead with a transfer and it would fail." 

Kirsten did her research, and discovered that close enough actually wasn't good enough. 

Despite raising concerns, her specialist dismissed them. "She didn't really have any insights. Just kept saying, 'Well, you know, people do fall pregnant with thin lining. Let's keep trying.'"

Kirsten trusted her instincts and switched doctors. "It was actually that very first appointment that he said to us, 'You know, thin linings are rare. They're often difficult to treat, and your best chance of having a baby is through surrogacy'."

"The container of embryos is empty."

They started the surrogacy process in Canada, shipping their final two embryos across the world. They matched with a surrogate named Julie and flew over for the transfer.

"We transported our embryos from Melbourne to Toronto for the surrogacy, and we did fly over for the first transfer. We were all sitting in the waiting room, and the transfer time came and went."

Eventually, a nurse came out to escort Kirsten, Ryan and Julie to the specialist's office.

"He said, 'I'm so sorry, but the container of embryos that you transported across from Australia is empty.'"

Their embryos were gone.

"Transporting embryos is a very standard common practice. What happened to us was extremely rare, less than 1 per cent chance of happening.

"At the time, I thought, this is the universe's way of saying we're not meant to be parents."

They were devastated, but not defeated. Kirsten went through another egg retrieval, created new embryos, and tried three more transfers in Canada. All three failed. 

"We just had an instant rapport."

The couple then turned to the US. "We went through the Utah Fertility Centre who were amazing. They really empathised with everything we'd been through, and they didn't rush us at all."

They were matched through a boutique agency with a new surrogate, Leah. "The first Skype that we had with our surrogate, Leah, and her husband, Josh, we just had an instant rapport and connection with them. It felt like we'd known each other forever."

The first transfer failed. The second worked. "We had a scan at seven and a half weeks, and everything was great. It was the furthest we'd ever got to at this point."

Two weeks later, they were due for the nine-week scan. Kirsten and Ryan decided to sleep through it and wait for Leah's messages.

"I woke up at 6am … and saw a WhatsApp message from Leah's husband, Josh, and all that said is, 'I'm so sorry. We've lost the baby.'"

They later found out it was a subchorionic hematoma. "They can't be prevented. They can't be treated."

"Once again, I was thinking, Oh, this is the universe's way of saying we're not meant to be parents."

But there was one embryo left. "There was one transfer left in the contract. So one final try."

It worked. "Nine months later, Spencer was born."

Baby Spencer was born via surrogacy. Image: Supplied.

"We owe her everything."

Kirsten and Ryan moved to Utah two weeks before the birth and stayed with Leah's family. 

"We actually lived with Leah and her husband, Josh, and their two boys for five weeks."

Spencer was born via vaginal birth. Kirsten was in the room with her mum.

"I just remember our obstetrician like, you know, get Spencer out. And he was like, 'Do you want to hold him?' We just walk over, I'm crying. And so I had the first skin-on-skin contact. Ryan cut the cord. Leah then had some skin-on-skin contact."

Kirsten says she didn't feel completely calm until her baby was in her arms. "Even though I definitely felt better at 12 weeks and I felt better again at 20 weeks and I felt better again at 30 weeks… until Spencer was actually born and I held him in my arms, I didn't feel 100 per cent joy, to be honest."

After the birth, Leah experienced a postpartum haemorrhage and preeclampsia — the same complications she'd had in a previous pregnancy. She knew the risks. 

"She absolutely did risk her life to help another family have a child.

"If it wasn't for her, we wouldn't have our son, we wouldn't have a family. So, you know, we owe her everything."

Feature image: Supplied.